The spat follows comments published by top Brunello producer Angelo Gaja and former Banfi winemaker Ezio Rivella.

Gaja said that, had Brunello estates been illegally blending other grapes to their wines, they should lobby to have the appellation rules changed. Brunello di Montalcino is nominally made from 100% Sangiovese, although some estates are suspected by the Italian authorities of having blended other grapes in with their wines.

Other producers in the region, 80km south of Florence, have reacted angrily to Gaja’s suggestions.

‘It’s high time to stop these declarations that propose changing Brunello’s production code to allow grapes other than Sangiovese,’ said Francesco Marone Cinzano, proprietor of Col d’Orcia and former president of the local Consorzio.

Marone Cinzano added that the ‘vast majority’ of producers wanted to ‘keep Brunello just as it is’.

There have been calls, however, for the strict regulations applied to Rosso di Montalcino, the region’s second wine, to be relaxed.

Franco Biondi Santi, whose pioneering grandfather Ferruccio is credited with inventing Brunello in the 1880s, suggested that parts of the region were not ideal for Sangiovese.

‘In some areas the vine excels, in others it simply does not,’ he said. ‘Rather than change Brunello, we should think about allowing other red grapes, grown within the denomination, to Rosso di Montalcino.’

According to local sources, Biondi Santi’s suggestion has found favour among the majority of Montalcino’s producers.

‘I do agree with Biondi Santi’s proposal of relaxing the rigid restrictions on Rosso di Montalcino. But Brunello must stay as it is,’ said Marone Cinzano.

An assembly will shortly be called in an attempt to put an end to the speculation on Brunello’s future.